Yes, this CR needs to continue. Alastor is thoroughly charmed by Namine. If anything happens to her, run.

Witch's Brew quest seems like a good way for them to hang out. He can teach her about herbs and stuff. Maybe pack some lunch so they can stray farther from town for more plants.

Bleeding Heart shenanigans would also be fun! Though I'm not sure which direction these two would go: Alastor producing a Bleeding Heart or Namine infected by one. Though if we wanted to be truly awful it could be Alastor produces the one that infects Namine. XD